Absorbent core for disposable absorbent articles with increased absorption rate and improved integrity

ABSTRACT

The present disclosure invention relates to a disposable absorbent article ( 100 ) comprising a liquid-pervious topsheet ( 10 ), a liquid-impervious backsheet ( 20 ) and an absorbent assembly ( 30 ) between the topsheet ( 10 ) and the backsheet ( 20 ). The absorbent assembly ( 30 ) comprises an absorbent core ( 40 ), an upper core wrap ( 50 ) and a lower core wrap ( 60 ). The absorbent core ( 40 ) comprises at least two cavities ( 70 ) free of absorbent material wherein the upper core wrap ( 50 ) and the lower core wrap ( 60 ) are permanently attached to each other, said cavities ( 70 ) being interconnected via at least one connecting line ( 80 ) comprising absorbent material. The absorbent core ( 40 ) has a first basis weight in the zone out of the cavities ( 70 ) and the connecting lines ( 80 ) and a second basis weight in the connecting lines ( 80 ), the first basis weight being greater than the second basis weight. in the cavities ( 70 ). The resulting absorbent assembly ( 30 ) may show all together a very good integrity, a very good distribution of fluids and a quick rate of absorption.

FIELD OF THE INVENTION

This disclosure pertains to the technical field of disposable absorbentarticles such as sanitary napkins, panty liners, baby diapers, babypants, adult diapers, adult pants, adult incontinence pads, etc., havingan absorbent assembly with improved integrity, lower return of liquidsto the surface (rewet), improved distribution of fluids and a quick rateof absorption.

BACKGROUND

The disposable absorbent articles are articles which are used inproximity with the skin of a wearer to absorb and retain body exudates;they are basically constituted by an upper liquid-pervious topsheet, abottom liquid impervious backsheet and an absorbent core disposedbetween them. The absorbent core of this kind of articles is generallycomposed of fibers of absorbent material and/or particles ofsuperabsorbent material; its main functions are to absorb and to retainliquid or semi-liquid exudates from the human body that penetratethrough the upper layer of the article. For the absorbent core beingeffective, it needs to have a good integrity, that is to say, theabsorbent core must maintain its structure and does not break orcollapse either in a dry or in a wet state. If said absorbent corebreaks, its absorption and retention capacity is lost and it is notcapable of distributing the fluids properly causing leakage,agglomerations of absorbent material and discomfort to the wearer.Multiple attempts have been made to prevent or minimize the structuralbreaks of the absorbent cores such as the use of nets, adhesives, corewraps, embossing and others. On the other hand, for an absorbent corehaving a good functionality, the fluids must be distributed properlyalong it in order to use its full absorbent capacity; it is alsorelevant that the fluids penetrate into the absorbent core as quickly aspossible in order to preserve the health of the skin of the wearer.

There are some patents focused on improving the integrity of theabsorbent cores, for example the U.S. Pat. Nos. 8,198,506 and 7,718,021(Kimberly Clark Worldwide Inc.) which disclose a stabilized absorbentcomposite web and the method for producing it; said absorbent compositecomprises a first sheetjoined to a second sheet through a plurality ofholes formed in the absorbent core. These patents are fully focused onimproving the integrity of the absorbent core sacrificing the ability toabsorb liquids more quickly as well as the ability to distribute themmore evenly and efficiently through the absorbent core.

On the other hand, there are several patents focused in improving thedistribution of fluids in the absorbent core using channels. For examplethe patents listed below refer to absorbent articles comprising anabsorbent core with an upper core wrap, a lower core wrap, a fibrouslayer and one or more areas free of absorbent material through which theupper core wrap joins to the lower core wrap, such that when theabsorbent material swells, the core wrap forms channels along the areasfree of absorbent material; these channels also help for having a goodrate of absorption of fluids into the core: U.S. Pat. Nos. 10,071,002,10,130,527, 9,789,009, 10,137,039, 10,335,324, 10,052,242, US 20180360671, US 2017 0135871, US2015 0080821.

There are some other patents referring to absorbent cores free ofcellulose fibers which improve the containment and retention capacity ofthe core, as for example US20150342796A1 from Procter & Gamble whichrefers to an absorbent core comprising a core wrap enclosingsuperabsorbent particles: the superabsorbent particles form a pattern ofdot-shape discrete areas which can be oriented longitudinally ortransversely; these areas are separated from each other by areassubstantially free of material and could also contain channels free ofabsorbent material. Absorbent cores as the one described in the referredpatent application are difficult to produce and are not soft enough forbeing comfortable to the user.

Other patents referring to absorbent cores divulge the use of zones withdifferent basis weight and density within the core. Depending the waythese zones are disposed, they are used for different purposes. Forexample, EP3238676B1 (Procter & Gamble) describes an absorbent core withfirst and second longitudinal channels free of absorbent material; thecore may further comprise one or more transverse oriented folding linesin which the basis weight of absorbent material reaches a minimumrelative to the immediately adjacent regions. These zones with lowerbasis weight are used only for facilitating the folding and as theyreach the longitudinal sides of the core, could also facilitate the flowof fluid promoting the run-off of liquid.

The present invention addresses the technical problems described aboveand provides an absorbent article with an absorbent assembly withimproved integrity which also improves the absorption rate, the rewetand the distribution of fluids inside it, expressed as the percentage ofuse of the absorbent core, said absorbent article having the features ofclaim 1. The at least one connecting line participates for improving thedistribution of fluids in the absorbent core. By combining in anabsorbent assembly (i) the cavities substantially free of absorbentmaterial, (ii) the at least one connecting line interconnecting thecavities and having absorbent material with a lower basis weight thanthe rest of the core (as taken outside of the cavities) and (iii) thepermanent bonding between the upper and lower core wraps, the resultingabsorbent assembly may show all together a very good integrity, a verygood distribution of fluids, a quick rate of absorption and a low rewet.

SUMMARY OF THE INVENTION

The present invention relates to a disposable absorbent article having alongitudinal direction and a transverse direction, the absorbent articlecomprising a liquid-pervious topsheet, a liquid-impervious backsheet andan absorbent assembly disposed between the topsheet and the backsheet.The absorbent assembly has two longitudinal edges, two transverse edges,a wearer-facing surface, a garment-facing surface, a longitudinalcentral axis extending along a length of the absorbent assembly and atransverse central axis defining a front portion and a back portion. Theabsorbent assembly comprises an absorbent core, an upper core wrap and alower core wrap. The absorbent core comprises absorbent materialcomprised by a mixture of superabsorbent polymer and cellulosic fibers.It further comprises at least two cavities free of absorbent materialhaving a width with respect to the transverse central axis and a lengthwith respect to the longitudinal central axis. Said cavities areinterconnected via at least one connecting line having a width withrespect to the transverse central axis and a length with respect to thelongitudinal central axis. The at least one connecting line comprisesabsorbent material. The absorbent core has a first basis weight in thezone out of the cavities and the connecting lines and a second basisweight in the connecting lines, the first basis weight being greaterthan the second basis weight. The upper core wrap and the lower corewrap are permanently attached to each other in the cavities.

In an embodiment of the invention, the at least two cavities of theabsorbent core may be aligned on the longitudinal central axis of theabsorbent assembly and be interconnected via at least one longitudinalconnecting line substantially parallel to the longitudinal central axis.

In an alternative embodiment of the invention, the cavities of theabsorbent core may form a pattern comprising two rows of at least twocavities, the cavities of each row being longitudinally interconnectedvia at least one longitudinal connecting line substantially parallel tothe longitudinal central axis, each row being disposed on each side ofthe longitudinal central axis. Both these patterns may provideparticularly advantageous integrity, distribution of fluids and quickrate of absorption.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a plan view of the wearer facing surface of a disposableabsorbent article according to the present invention in an extendedconfiguration.

FIG. 1A is a cross-sectional view of the disposable absorbent article ofFIG. 1 taken along the transverse central axis (X-X).

FIG. 2 representatively illustrates a plan view of the absorbentassembly of a disposable absorbent article according to an embodiment ofthe present invention.

FIG. 2 a is a longitudinal cross-sectional view of the absorbentassembly of FIG. 2 taken along the longitudinal central axis (Y-Y)

FIG. 3 Illustrates a plan view of an absorbent assembly of a disposableabsorbent article according to an embodiment of the present invention.

FIG. 4 shows a plan view of another embodiment of the absorbent assemblyof a disposable absorbent article according to the present invention.

FIGS. 5, 6, 7 and 8 show plan views of other embodiments of theabsorbent assembly of disposable absorbent articles according to thepresent invention.

FIG. 9 shows a plan view of a disposable absorbent article of the priorart (channeled diaper).

DETAILED DESCRIPTION OF THE INVENTION

All the terms used to define the elements and/or features of the presentinvention, including technical and scientific terms, have the meaning ascommonly understood by one of ordinary skill in the art to which thisinvention belongs.

As used herein, the following terms have the following meanings:

“Absorbent articles” refers to devices that absorb and contain bodyexudates, and, more specifically, refers to devices that are placedagainst or in proximity to the body of the wearer to absorb and containthe various exudates discharged from the body. Absorbent articlesinclude baby and adult diapers, baby and adult pants, adult incontinenceundergarments, feminine hygiene products, and the like.

“Topsheet” refers to a liquid permeable substrate forming the innercover of the absorbent article and which in use is placed in directcontact with the skin of the wearer. The topsheet can comprise anonwoven material made of natural or synthetic fibers or any mixture ofnatural or synthetic fibers and made by any method known in the art.

“Backsheet” refers to a liquid impermeable sheet forming the garmentfacing surface of the absorbent article. The backsheet prevents bodyfluids and exudates absorbed by the absorbent article for passingthrough it. The backsheet may comprise a thin plastic film such as athermoplastic film (e.g. a polyethylene or polypropylene film) or itcould be a laminate comprised by a thin impermeable film and a nonwovenweb. The materials which are commonly used as backsheets may includebreathable materials which permit vapors to pass through it stillpreventing, fluids for passing through the backsheet.

“Absorbent assembly” refers to the combination of an absorbent coreenclosed by at least one core wrap.

“Core wrap” refers to one or more substrate layers that enclose theabsorbent core and can comprise one or more layers of nonwoven materialmade of mono or bicomponent natural or synthetic fibers such as, but notlimited to polyester, polyethylene, polypropylene, viscose, rayon,cotton, polyhydroxyalkanoates, etc., they may comprise hydrophilicand/or hydrophobic treatments.

“Absorbent core” refers to a structure for the absorption andcontainment of body exudates, said absorbent core is comprised byabsorbent materials such as, but not limited to cellulosic fluff pulp,tissue layers, superabsorbent polymer particles (SAP), absorbent foammaterials, absorbent nonwoven materials or mixtures thereof; theabsorbent core can have any shape as for example a rectangular shape, ananatomical shape, an hourglass-shape, a “T” shape or any other one knownin the art.

“Cavities” refers to areas substantially free of absorbent materiallocated in the absorbent core.

“Connecting lines” refers to substantially rectilinear regions thatinterconnect at least two cavities to each other. Contrary to thecavities, the connecting lines contain some absorbent material having alower basis weight than the rest of the absorbent core.

“Attached” refers to the relationship between two or more elements,which can be joined to each other in any known way, such as but notlimited to ultrasonic bonding, mechanical bonding, thermal bonding, byadhesives, or the like.

Embodiments of articles according to the present invention will now bedescribed, from here on, in relation to a disposable diaper, but it isunderstood that the absorbent article may be selected from disposablediapers, disposable adult pants, disposable baby pants, adultincontinence pads, sanitary napkins and the like. The technical featuresdescribed in one or more embodiments may be combined with one or moreother embodiments without departing from the intention of the disclosureand without generalization thereof.

FIG. 1 illustrates a wearer facing surface of a disposable absorbentarticle (100) according to an embodiment of the present invention in anextended configuration. As can be seen, the disposable absorbent article(100) comprises basically a liquid-pervious topsheet (10), aliquid-impervious backsheet (20) and an absorbent assembly (30) placedbetween them. The disposable absorbent article comprises two oppositelongitudinal sides and two opposite transverse sides; the disposableabsorbent article (100) can also contain a fastening system, leg andwaist elastic zones, front and back ears, transfer layers, containmentbarriers and other elements well known in the art.

FIG. 1A shows a transverse cross-section of the disposable absorbentarticle of FIG. 1 taken along the transverse central axis (X-X). Thedisposable absorbent article (100) comprises a liquid-pervious topsheet(10), an absorbent assembly (30) and a backsheet (20); the absorbentassembly (30) is constituted by an upper core wrap (50), an absorbentcore (40) and a lower core wrap (60).

The absorbent assembly (30) has two longitudinal edges (41, 41′), twotransverse edges (42, 42′), a wearer-facing surface (43), agarment-facing surface (44), a longitudinal central axis (Y-Y) and atransverse central axis (X-X). The longitudinal central axis (Y-Y)extends along the length of the absorbent assembly (30) so that itdefines a left side and a right side, each one of said sides having asubstantially equal transverse width; the transverse central axis (X-X)extends along the width of the absorbent assembly (30) defining a frontportion (45) and a back portion (46), each one of said portions having asubstantially equal length. The absorbent core (40) of the inventioncomprises at least two cavities (70) and at least one connecting line(80) interconnecting them.

Said absorbent core (40) is comprised of absorbent material which iscomposed preferably of a mixture of superabsorbent polymer particles(SAP) and cellulosic fibers which could be replaced by other fibers ofabsorbent material of natural or synthetic origin. The superabsorbentpolymer particles are able to absorb and retain fluids many times theirown weight and may be in the form of particles, fibers, flakes or thelike.

The cavities (70), as are shown for example in FIG. 2 , are areassubstantially free of absorbent material and have a width (W1) intransverse direction and a length (L1) in longitudinal direction. Thecavities (70) may contain a minimum quantity of absorbent material,mainly because of some contamination during the manufacturing process.

Advantageously, cavities according to the invention may have an areabetween 50 mm² and 2500 mm², preferably between 100 mm² and 2000 mm²,more preferably between 150 mm² and 1500 mm².

Preferably, the cavities (70) of the invention are longitudinally spacedfrom each other by a distance between 5 mm and 250 mm, more preferablybetween 10 mm and 200 mm, even more preferably between 10 mm and 150 mmor between 15 mm and 150 mm. Advantageously, they are transverselyspaced from each other by a distance between 5 mm and 250 mm, morepreferably between 10 mm and 200 mm, even more preferably between 10 mmand 150 mm or between 15 mm and 150 mm. These distances between thecavities corresponds to the shortest distance between the perimeter ofone cavity and the perimeter of the next cavity in longitudinal ortransverse direction. The distance in longitudinal direction between twoneighboring cavities (70) may correspond to the length (L2) of aconnecting line (80).

In a preferred embodiment, the cavities (70) have a circular shape butalternatively, they may have a shape selected from the group consistingof triangles, squares, rectangles, polygons, ovals, semicircles, arrows,crosses, irregular shapes and combinations thereof.

As the upper and lower core wraps are permanently attached in thesecavities, the absorbent material between each cavity is immobilizedthereby helping in maintaining the integrity of the absorbent core (40).These dimensions and shapes have proven to help in providing thisintegrity.

One function of the at least one connecting line (80) is to spread ordistribute the fluids effectively throughout the absorbent core (40),thereby helping in increasing the absorption rate and better using allthe absorption capacity of the absorbent core. Each connecting line hasa width (W2) with respect to the transverse direction and a length (L2)with respect to the longitudinal direction, as can be seen in FIG. 2 .The ratio (W2/W1) between the transverse width of the connecting line(W2) and the transverse width of the cavities substantially free ofabsorbent material (W1) is preferably at most 1, more preferably at most0.9, even more preferably at most 0.8, so that when a fluid reaches acavity, it passes quickly through the connecting line(s) directly toanother cavity helping in distributing the fluid in the absorbent core.

The absorbent core (40) of the present invention has a first basisweight (bw1) outside the cavities (70) and the connecting line (80), anda second basis weight (bw2) in the connecting line (80). The first basisweight (bw1) is greater than the second basis weight (bw2). Preferably,the ratio (bw2/bw1) between the second basis weight (bw2) and the firstbasis weight (bw1) is between 0.25 and 0.95, more preferably between0.35 and 0.85, even more preferably between 0.45 and 0.75. These ratiosare advantageous in that the fluid may be transported more quickly inthe areas having less basis weight. For this reason, the distribution offluid inside the absorbent core (40) of the present invention may beimproved compared with the distribution of fluids in an absorbent core(40) having a constant basis weight. In addition, as the fluid is betterdistributed, it does not accumulate in small zones and as a result ofthis, the rewet may be lowered. On the other side, the cavities (70) inconjunction with the connecting line (80) may help for the absorbentassembly (30) having a fast rate of absorption and/or in directing thefluid in order to use all the absorption capacity of the core (40).

In preferred embodiments of the present invention, the upper core wrap(50) is permanently attached to the lower core wrap (60) in the cavities(70) by means of adhesive, thermal bonding, pressure bonding, mechanicalbonding, ultrasonic bonding or combinations thereof or any other meansknown in the art. The permanent attachment between the upper core wrap(50) and the lower core wrap (60) in the cavities (70) defines bondingzones (90), as can be seen in FIG. 2 a which may contribute to theabsorbent assembly (30) having a very good integrity given that theabsorbent material is immobilized between the cavities (70). The uppercore wrap and lower core wrap (50, 60) are preferably nonwoven webs madefrom natural or synthetic fibers and/or combinations thereof; they canbe composed of one or more layers bonded together and can bemanufactured by any known method. The upper core wrap (50) is preferablya hydrophilic nonwoven web having a basis weight between 5 g/m² and 20g/m². The lower core wrap (60) could be a hydrophobic or a hydrophilicnonwoven web having a basis weight between about 5 g/m² and 20 g/m².

In an embodiment of the present invention shown in FIG. 3 , ninecavities (70) are aligned on the longitudinal central axis (Y-Y) of theabsorbent assembly (30), and are interconnected via at least eightlongitudinal connecting lines (80), said connecting lines (80) being onthe longitudinal central axis (Y-Y).

Another embodiment of the present invention is shown in FIG. 4 . In thisembodiment, six cavities (70) have an arrow-shape and are aligned on thelongitudinal central axis of the absorbent assembly (30), such that, thearrow-shaped cavities (70) point toward the transverse edges of theabsorbent assembly (30). Said cavities (70) are interconnected throughfive longitudinal connection lines (80) on the longitudinal central axis(Y-Y).

FIG. 5 shows another embodiment of the present invention in which thecavities (70) are disposed in the absorbent core (40) forming a pattern,said pattern comprising two rows of two cavities (70) beinginterconnected via one longitudinal connecting lines (80). Each row isdisposed on each side of the longitudinal central axis (Y-Y) of theabsorbent assembly (30) and parallel to it. The connecting lines (80)are substantially parallel to the longitudinal central axis (Y-Y).

FIG. 6 shows another embodiment of the present invention in which thecavities (70) form a pattern comprising four rows. Each row comprises atleast two cavities (70) interconnected via at least one connecting line(80), one row being disposed in the front right quarter of the absorbentassembly (30), the second one being disposed in the front left quarterof the absorbent assembly (30), the third one in the back right quarterof the absorbent assembly (30) and the fourth row in the back leftquarter of the absorbent assembly (30) respectively. The first row isinterconnected to the fourth row via at least one connecting line (80)and the second row is interconnected to the third row via at least oneconnecting line (80), such that, these connecting lines (80) form anX-shaped pattern.

FIG. 7 shows another embodiment of the present invention in which, thecavities (70) are disposed in the absorbent core (40) forming ahexagonal pattern, said hexagonal pattern comprising six cavities (70)coinciding with the apex of the hexagonal pattern, and a plurality ofconnecting lines (80) connecting the cavities (70) such that, theconnecting lines (80) define the outer perimeter of the hexagonalpattern.

In some embodiments of the invention, one or more connecting lines (80)may comprise regions having the second basis weight (bw2) and otherregions having a third basis weight (bw3), so that the first basisweight (bw1) is greater than the second basis weight (bw2), and thesecond basis weight (bw2) is greater than the third basis weight (bw3).In this way the fluid may run in the connecting lines at varying speed,helping the absorbent assembly (30) to be more efficient in the rate ofabsorption and in the distribution of fluids.

The cavities (70) may be distributed in the absorbent core forming anypattern. As the discharge of fluids into the absorbent article is madegenerally in the front portion (45) of the absorbent assembly (30), thisfront portion (45) is the one that tends to first loss the integrity,thereby losing its capability to absorb and distribute the fluids.Therefore, in a preferred embodiment, more than 50% of the total area ofthe cavities (70) is disposed in the front portion of the absorbentassembly (30). The total area of the cavities is obtained by adding theindividual area of each cavity (70).

Test Methods

Rate of Absorption, Percentage of Use of the Absorbent Core and Rewet

Materials:

-   -   Synthetic urine (0.9% saline solution)    -   Universal support    -   Semi-analytical balance with precision of 0.01 g;    -   Calculator    -   Stopwatch    -   Metal scale    -   Separation funnel 125 mL (7 mL/s or equivalent);    -   Tissue paper previously cut to square 100 mm×100 mm;    -   Test tube 100 ml;    -   Stainless steel dosing ring (internal 0 53 mm/height 50 mm and        wall thickness 3 mm);    -   Weight 2.5 kg (external 0 76 mm and height 70 mm);    -   Disposable absorbent articles    -   Separation funnel fitting ring with internal 0 55 mm

Procedure:

-   -   1. Prepare the synthetic urine.    -   2. Stack and weigh an amount of absorbent paper, according to        the values measured in table 1.    -   3. Record the weight (Dry weight of the absorbent paper) to        measure the fluid returns (first, second and third);    -   4. Measure the absorbent core length and record this length.    -   5. Cut and remove the leg elastics to keep the product taut. For        underwear, tear the side seal of the product and use scissors to        cut the outline of the polyethylene film. Then position/stick        the product with the outer side on an acrylic plate with hook        strips at the ends to keep the product straight.    -   6. Mark the insult zone in the disposable absorbent article        (drawing an horizontal line on the frontal portion of the        disposable absorbent article at a distance of 5.0 cm to the        transverse central axis (X-X) and position the dosing ring over        the horizontal line and aligned with the longitudinal central        axis (Y-Y). The zone inside the dosing ring is the insult zone.    -   7. For each disposable absorbent article/size analyzed, measure        an amount of synthetic urine (showed in Table 2, Table 3) and        place it in the funnel.    -   8. Place the tip of the funnel about 1.0 cm from the top end of        the dosing ring.    -   9. Open the funnel valve and start the timer when the liquid        contacts the product, stop the timer as soon as all the        synthetic urine is absorbed and record the time as the primary        acquisition time (first time).    -   10. Once all synthetic urine has been absorbed, wait 10 minutes        and place the previously weighed 15.0 g absorbent paper stack        centered over the marked area of insult, put the 2.50 kg weight        on the absorbent paper stack and wait for 2 minutes. Mark the        point at the front and back portions of the absorbent core as        far as the liquid went, measure the length of the stain created        by the synthetic urine, record the length as the primary fluid        distribution (first distribution).    -   11. After 2 minutes, remove the weight of 2.50 kg, weigh and        record the weight of the absorbent paper stack (wet weight);    -   12. Repeat the previous steps to measure the second and third        return, distribution and time. (The laboratory test must be        carried out with 5 different samples, then the values obtained        are averaged in order to have a reliable result.)

Return (g)=Weight of the absorbent paper (g)−Dry weight of the absorbentpaper (g)

Rate of absorption (ml/s)=Amount of synthetic urine (ml)/time ofabsorption (s).

Total distribution (mm)=Third measured length of the stain (mm).

Percentage of use of the absorbent core=[Total distribution(mm)*100]/Length of the core (mm)

Preparation of the Synthetic Urine

-   -   2 L volumetric flask;    -   Coloring;    -   Sodium chloride;    -   Deionized water.

Procedure:

-   -   1. Weigh 18 g of sodium chloride and transfer to a 2.0 L        volumetric flask.    -   2. Dissolve and complete to volume with deionized water.    -   3. Add a small portion of coloring to the solution

The saline solution should be prepared 4 hours before the test; itsshelf life is up to 7 days.

Tables

TABLE 1 Absorbent paper weight Primary Return  15.0 g (+/− 0.5 g)Secondary Return  30.0 g (+/− 0.5 g) Tertiary Return  3000 g (+/− 0.5 g)

TABLE 2 Infants Size Newborn Small Medium Large XL XXL Quantity 40 40 6080 100 100 (ml.)

TABLE 3 Adults Size Youth Small Medium Large XL Quantity 40 40 60 80 100(ml.)

Examples

Embodiment A (not according to the invention): Disposable absorbent babydiaper size “L” containing an absorbent assembly comprising:

-   -   an upper core wrap and a lower core wrap having a basis weight        of 8 g/m² each and    -   an absorbent core without cavities and connecting lines        containing 7 g of cellulosic fibers and 10.5 g of superabsorbent        polymer (SAP) and having a basis weight (bw1) of 505.56 g/m².

Embodiment B (according to the invention): Disposable absorbent babydiaper size “L” containing an absorbent assembly comprising:

-   -   an upper core wrap and a lower core wrap having a basis weight        of 8 g/m² each one and    -   an absorbent core containing 7 g of cellulosic fibers and 10.5 g        of superabsorbent polymer (SAP) and having six bar shaped        cavities (70) [each one with an area of around 306 mm²] aligned        on the longitudinal central axis (Y-Y) interconnected via five        longitudinal connecting lines (80). The absorbent core has a        basis weight (bw1) of 397 g/m² and each one of the connecting        lines has a basis weight (bw2) of 291.12 g/m².

Embodiment C (according to the invention): Disposable absorbent babydiaper size “L” containing an absorbent assembly comprising:

-   -   an upper core wrap and a lower core wrap each one having a basis        weight of 8 g/m² and    -   an absorbent core containing 7 g of cellulosic fibers and 10.5 g        of superabsorbent polymer (SAP) and having six arrow-shaped        cavities (70) [each one with an area of around 378 mm²] aligned        on the longitudinal central axis (Y-Y) interconnected via five        longitudinal connecting lines (80). The absorbent core has a        basis weight (bw1) of 557 g/m² and each one of the connecting        lines has a basis weight (bw2) of 339 g/m².

Embodiment D (according to the invention and as illustrated in FIG. 8 ):Disposable absorbent baby diaper size “L” containing an absorbentassembly comprising:

-   -   an upper core wrap and a lower core wrap each one having a basis        weight of 8 g/m² and    -   an absorbent core containing 7 g of cellulosic fibers and 10.5 g        of superabsorbent polymer (SAP) and having 2 rows of three        dot-shaped cavities (70) [each dot-shaped cavity having an area        of around 159 mm²], each row being disposed at each side of the        longitudinal central axis (Y-Y), having 2 connecting lines (80)        connecting the 3 cavities of each row. The absorbent core has a        basis weight (bw1) of 557 g/m² and each one of the connecting        lines has a basis weight (bw2) of 339 g/m².

Pampers Confort Sec® (as illustrated in FIG. 9 ) size “L” having anabsorbent assembly comprising:

-   -   an upper core having a basis weight of 9 g/m² and a lower core        wrap having a basis weight of 12 g/m²; and    -   an absorbent core containing 4 g of cellulosic fibers and 7.5 g        of superabsorbent polymer (SAP) and having 2 channels [each        channel having a length of around 180 mm and a width of around 8        mm] substantially free of absorbent material and being disposed        at each side of the longitudinal central axis (Y-Y). The        absorbent core has a basis weight of around 275 g/m².

Table 4 shows the results obtained for embodiments A, B and C describedabove.

TABLE 4 EMBODIMENT EMBODIMENT EMBODIMENT A B C Total absorption 2.104.34 3.47 rate after three insults (ml/s) Rewet after three 20.55 13.058.46 insults. (g) Total distribution 235.4 262.6 276.0 length afterthree insults. (mm) Percentage of use 65 73 77 of the absorbent core.(%)

These results show that the absorption rate of embodiment B is around20% faster than the absorption rate of embodiment A, and the absorptionrate of embodiment C is around 30% faster than the absorption rate ofembodiment A. The return of fluids to the surface of the diaper (rewet)of embodiment B is around 35% lower than the rewet of embodiment A andthe rewet of embodiment C is around 60% lower than the rewet ofembodiment A. The percentage of use of the absorbent core of embodimentB is around 15% greater than the percentage of use of the absorbent coreof embodiment A and finally the percentage of use of the absorbent coreof embodiment C is around 20% greater than the percentage of use of theabsorbent core of embodiment A. Accordingly, the embodiments B and C ofthe present invention have a better performance than embodiment A of theprior art.

On the other hand, Table 5 shows the results obtained in Embodiment D ofthe present invention compared with a channeled diaper available on themarket (Pampers Confort Sec®).

TABLE 5 EMBODIMENT Pampers D Confort Sec ® Total absorption rate after6.89 8.88 three insults (ml/s) Rewet after three insults. (g) 7.02 20.78Total distribution length after 285.6 279 three insults. (mm) Percentageof use of the 79.33 77.5 absorbent core. (%)

As shown in Table 5, the rewet of Embodiment D is substantially lessthan the rewet of Pampers Confort Sec®, which keeps the wearer's skindry and free from irritations; the percentage of use of the absorbentcore of the embodiment D shows a better performance in comparison withPampers Confort Sec®. Finally the absorption rate of Pampers ConfortSec® seems slightly better with respect to embodiment D, however,according to experts in the art, a difference of 2 seconds in absorptionrate is not significant for this feature.

1.-12. (canceled)
 13. A disposable absorbent article comprising: aliquid-pervious topsheet; a liquid-impervious backsheet; and anabsorbent assembly disposed between the topsheet and the backsheet, andhaving a transverse central axis (X-X) and a longitudinal central axis(Y-Y); wherein the absorbent assembly comprises an upper core wrap, alower core wrap, and an absorbent core disposed at least partiallybetween the upper and lower core wraps; wherein the absorbent corecomprises absorbent material comprising a mixture of superabsorbentpolymer and cellulosic fibers, and has at least two cavities that aresubstantially free of absorbent material and interconnected by at leastone connecting line; wherein each of the at least one connecting linecomprises absorbent material; wherein the absorbent core has a firstbasis weight (bw1) in a zone outside of the cavities and the at leastone connecting lines, and a second basis weight (bw2) within the atleast one connecting line, and the first basis weight (bw1) is greaterthan the second basis weight (bw2); wherein the upper core wrap ispermanently attached to the lower core wrap in each of the cavities; andwherein at least two of the cavities are substantially aligned in alongitudinal direction, parallel to the longitudinal central axis (Y-Y)of the absorbent assembly.
 14. The disposable absorbent article of claim13, wherein at least two of the cavities and at least one of theconnecting lines are substantially aligned on the longitudinal centralaxis (Y-Y) of the absorbent assembly.
 15. The disposable absorbentarticle of claim 13, wherein at least two of the cavities arelongitudinally spaced apart from each other by a distance of 5 mm to 250mm.
 16. The disposable absorbent article of claim 13, wherein at leasttwo of the cavities are transversely spaced apart from each other by adistance of 5 mm to 250 mm.
 17. The disposable absorbent article ofclaim 13, wherein at least two of the cavities are longitudinally andtransversely spaced apart from each other.
 18. The disposable absorbentarticle of claim 13, comprising at least one transversely-extendingconnecting line that extends at least partially in the transversedirection and interconnects two cavities that are transversely spacedapart.
 19. The disposable absorbent article of claim 18, comprising atleast a first and a second transversely-extending connecting line thatextend at least partially in the transverse direction, wherein the firsttransversely-extending connecting line intersects the secondtransversely-extending connecting line.
 20. The disposable absorbentarticle of claim 18, wherein the at least one transversely-extendingconnecting line traverses the longitudinal central axis (Y-Y).
 21. Thedisposable absorbent article of claim 13, wherein the at least twocavities are arranged to form a pattern, the pattern comprising aplurality of longitudinally-extending rows, eachlongitudinally-extending row comprising at least two cavities that aresubstantially aligned in the longitudinal direction.
 22. The disposableabsorbent article of claim 21, comprising two longitudinally-extendingrows, each row being disposed on opposing sides of the longitudinalcentral axis (Y-Y).
 23. The disposable absorbent article of claim 21,wherein each of the longitudinally-extending rows comprises at least twolongitudinally-adjacent cavities that are interconnected by at least oneconnecting line, and said adjacent cavities and connecting lines aresubstantially aligned in the longitudinal direction.
 24. The disposableabsorbent article of claim 21, wherein within each of thelongitudinally-extending rows, at least two longitudinally-adjacentcavities are not interconnected with each other.
 25. The disposableabsorbent article of claim 21, comprising at least onetransversely-extending connecting line that extends at least partiallyin the transverse direction and interconnects at least one cavity in afirst longitudinally-extending row with at least one cavity in a secondlongitudinally-extending row.
 26. The disposable absorbent article ofclaim 25, comprising two or more transversely-extending connectinglines.
 27. The disposable absorbent article of claim 26, wherein two ofthe transversely-extending connecting lines intersect each other. 28.The disposable absorbent article according to claim 13, wherein each ofthe two or more cavities independently has a shape selected from thegroup consisting of triangle, square, rectangle, polygon, circle, oval,semi-circle, arrow-shape, cross, irregular shape and combinationsthereof.
 29. The disposable absorbent article according to claim 13,wherein each of the two or more cavities has an area between 50 mm² and2500 mm².
 30. The disposable absorbent article according to claim 13,wherein the absorbent core has a total cavity area that is the sum ofall of the respective areas of the two or more cavities, and more than50% of the total cavity area is disposed in a front portion of theabsorbent assembly, forward of the transverse central axis (X-X) of theabsorbent assembly.
 31. The disposable absorbent article of claim 13,wherein at least two cavities have a transverse width (W1) measured in atransverse direction of the absorbent assembly, and at least oneconnecting line interconnecting the at least two cavities has atransverse width (W2) measured in the transverse direction of theabsorbent assembly, and a ratio (W2/W1) between the width (W2) of the atleast one connecting line and the width (W1) of the cavities is atmost
 1. 32. The disposable absorbent article of claim 13, wherein aratio (bw2/bw1) of the second basis weight (bw2) to the first basisweight (bw1) is between 0.25 and 0.95.
 33. The disposable absorbentarticle of claim 13, wherein the upper core wrap is permanently attachedto the lower core wrap in the cavities by means of adhesive bonding,thermal bonding, pressure bonding, mechanical bonding, ultrasonicbonding or combinations thereof.
 34. The disposable absorbent article ofclaim 13, wherein said disposable absorbent article is selected from thegroup consisting of baby diapers, adult diapers, baby pants, adultpants, adult incontinence undergarments or pads, sanitary napkins andpanty liners.
 35. The disposable absorbent article of claim 13, whereinthe absorbent core comprises six cavities arranged to form a hexagonalpattern, such that each cavity coincides with an apex of the hexagonalpattern, and adjacent cavities are interconnected by at least oneconnecting line.